@EThought113213 2 shots from a mastff and you've killed the person. That's no different than a peace keeper. I believe the fire rate of the mastiff is slightly quicker than the PK but the recoil might be worse. It's been a while since I've picked one up. Honestly I rarely pick up care package guns, I like the guns I have and have no issue killing players who run other guns.
Hemlock is a solid gun. I down players in 1 burst with the hemlock once their shields are broken. 2-3 burst to down a player with a hemlock, so long as you land your shots and get a few head shots in with each burst (which is not difficult to do).
G7 is a solid gun as well if you use it right. I typically run a Hemlock PK, Hemlock G7, PK G7 or some combo of the 3 guns. But I will also use the R-301, Wingman is a work in progress (not accurate enough yet).
One thing that I've noticed from players who don't like certain guns.. They get stuck playing with the same load outs again and again and again.. Each gun has benefits and draw backs IMO. But if you play to the guns strong points you'll win.